Pumpkin powder for performance (say that 5 times fast!)

November 29, 2012

Just in time for Fall Feedings!

What enjoyment people ever got out of smashing pumpkins (not the grunge band Smashing Pumpkins, they were awesome) I will never understand, especially when you consider how tasty and health promoting they happen to be. The flesh from pumpkin fruit provides a variety of essential major, minor and trace minerals, including calcium, phosphorus, magnesium, potassium, and iron, and also zinc, selenium, copper, chromium, and nicotinic acid (Kim et al., 2012). Additionally, pumpkin flesh contains phytocompounds with anti-inflammatory and anti-lipogenic (making pumpkin a great addition to chili peppers) effects (Hadad & Levy, 2012; Lee et al., 2012). Pumpkin flesh is not only healthy; it also appears to have ergogenic qualities.

Wang et al. (2012) investigated the effects of pumpkin extract (PE) on endurance, metabolic markers, and grip strength in mice. Mice were supplement with either a placebo or 3 different doses of PE for 2 weeks and then exercises to fatigue via swimming. Prior to and following supplementation pre and post exercise blood was sampled and analyzed for lactate, nitrogen ammonia (NH3) glucose, and creatine kinase. Additionally, muscle biopsies were taken and analyzed for glycogen.

The mice supplemented with PE swam nearly twice as long compared to placebo (4.63 vs. 7.98 min). There are a few mechanisms as to how PE improved endurance. First, PE supplementation increased muscle glycogen stores and preserved blood glucose during exercise. Since more energy can be generated from glycogen than blood glucose, this may suggest that PE increase glycolytic efficiency. On the other hand, Wang et al. reported a reduction in lactate with PE. If we use lactate as a (weak) determinant of glycolysis, then PE did not increase glycolysis, but likely increased fatty acid oxidation; however, we can only speculate at this point since Wang et al. did not measure post exercise muscle glycogen or fatty acid oxidation.

Interestingly, PE decreased post exercise plasma ammonia. Given that NH3 is linked to the development of muscular fatigue, especially in fast twitch muscle fibers (Mutch & Banister, 1983), PE may have helped sustain power output. Although Wang et al. did not measure power output decrements; the researchers did report an increase in grip strength with PE. Additionally, plasma creatine kinase, a marker of muscle damage, was reduced post-exercise for PE compared to placebo.

Given then reduction in NH3 (and possibly fast twitch fiber fatigue rates), creatine kinase, and increase in grip strength; PE may be a useful supplement to improve strength/power performance and improve recovery time. More research of course is needed to test this theory in humans; however, the method of pumpkin extraction and the dose given (50-100 mg/kg) is quite easily replicable, and makes this an interesting potential sports supplement.